Elastic and elastomeric fibers and yarns are known. Examples include spandex and rubber. However, these typical elastic yarns suffer from many disadvantages. Natural rubber has limitations such as availability only heavy deniers and limited suitability for apparel due to potential for latex allergy.
Spandex yarns have excellent stretch and recovery, but are costly to manufacture. Also, spandex is vulnerable to chemical and environmental conditions such as exposure to chlorine, nitrogen oxides (NOx, where x is 1 or 2), fumes, UV, and ozone among others.
Currently available polyolefin elastomers have low elongation/stretch, very low recovery power and high set (growth) making them unsuitable for typical apparel stretch fabric applications.
U.S. Patent Application Publication 2009/0298964 discloses a polyolefin composition that is spun into a yarn, but these yarns are unsuitable for apparel fabrics due to limited elongation, reaching a maximum of 195%.